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Ors, Alvaro d'. 1947. 'ERNST LEVY: Principal and Surety in classical Roman Law. De «Seminar», 2, Wáshington, 1944. BOAZ COHEN: Some Remarks on the Law of Persons in Jewish and Roman Jurisprudence. En "Procedings of the America Academy for Jewih Research", vol. 16, 1947 (separata).'. ANUARIO DE HISTORIA DEL DERECHO ESPAÑOL. pp. 934-934.
